The question is pertinent for researchers in the field of consumer psychology where there's a tendency to apply theories and measures from the study of interpersonal love to the study of brand attachment, as if the emotions are equivalent.

A new paper investigated people's feelings for their favourite brands by recording their physiological arousal levels (based on sweatiness of the skin) while they looked at pictures of the logo for a brand they said they love (such as Adidas, Audi and BMW), as compared with with their arousal while they looked at pictures of a romantic partner they love, and at their closest friend. The 20 participants also used a visual rating scale (mannequins pulling different facial expressions) to indicate the feelings triggered by their romantic partner, their friend and the brand they love.

The physiological readings and subjective ratings indicated that people's love for the partner is much more intense than their love for their favourite brand. Tobias Langner and his team predicted this result and said it shows romantic love and brand love "constitute different emotions". This interpretation was also supported by interviews the researchers conducted with 60 other participants: when people spoke of brand love, they did so much more in the context of an exchange (i.e .what they got from the brand), as compared with how they spoke of romantic love, which was often more altruistic in nature. Based on this, the researchers said scholars in their field should be cautious before continuing to transfer measures and theories from interpersonal love to brand love as if the two are synonymous.

And yet, the findings also suggest we should not underestimate the intensity of emotion some people feel for their favourite brands. The participants' physiological arousal in response to their loved brand logo was as intense as the arousal they showed when looking at a picture of their closest friend. And on the subjective rating scale for "valence" (featuring smiley and unhappy looking mannequins), the participants reported more positive feelings in response to the brand logo than the friend!

The small sample gives reason to treat this last finding with some scepticism, as does the fact that the participants were deliberately recruited on the basis that there was a consumer brand they really loved and could not live without. Bear in mind, however, that to qualify all participants also needed to be in a romantic relationship. Perhaps brand attachment could be even more intense for people not in love with a partner?